Journal of Irrigation and Drainage Engineering: Recent submissions
Now showing items 3681-3700 of 3826
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Emitter Spacing and Geometry of Wetted Soil Volume
(American Society of Civil Engineers, 1986)A method for determining width and depth of the wetted soil volume under an emitter is described. The proposed method is tested using computed and experimental results from a plane flow model. A procedure for computing ... -
Microcomputer Simulation of Canal Operation
(American Society of Civil Engineers, 1986)A computer model for the simulation of canal operation was developed. The model is applicable for any nonbranching canal system composed of a series of channels separated by control structures. The programming language ... -
Controlled Agricultural Drainage to Maintain Water Quality
(American Society of Civil Engineers, 1986)The effects of land clearing and drainage as well as effect of drainage system design and management upon hydrologic and water quality parameters were determined. The most dramatic effect of agricultural land development ... -
Clogging of Recharge Wells by Suspended Solids
(American Society of Civil Engineers, 1986)Field conditions have been reproduced in the laboratory in order to investigate the fundamentals governing the mechanism of clogging of recharge wells. Dosing with water of controlled quality and temperature, containing ... -
Demand Irrigation Schedule Pilot Project: Sri Lanka
(American Society of Civil Engineers, 1986)Since 1981, the Sri Lanka Government has been testing a different approach to delivering irrigation water to its numerous small‐scale farmers. Instead of conventional open‐channel rotation irrigation with water controlled ... -
Time of Concentration of Overland Flow
(American Society of Civil Engineers, 1986)A mathematical model based on kinematic overland flow and Green‐Ampt infiltration is developed to calculate the time of concentration of overland flow on a rectangular plane surface. The governing equations of the ... -
Derivation of Lewis‐Kostiakov Intake Equation
(American Society of Civil Engineers, 1986)The empirical Lewis‐Kostiakov intake equation takes a power form in an algebraic equation that explicitly relates the cumulative infiltration depth, -
Stochastic Modeling of Irrigation Requirements
(American Society of Civil Engineers, 1986)The objective of this paper is to study the stochastic structure of weekly irrigation requirement of a crop. The irrigation requirement time series is assumed to be represented by an additive model with trend, periodic and ... -
Optimal Water Management Strategies for Salinity Control
(American Society of Civil Engineers, 1986)Multi‐objective linear programming models have been formulated to evaluate the water management strategies for salinity control. The water management strategies essentially aim at minimizing irrigation return flow (IRF) ... -
On the Frequency Distribution of Raindrop Sizes
(American Society of Civil Engineers, 1986)Knowledge of the distribution of the raindrop sizes during a storm is important in many engineering applications. Since drop size information is usually expressed parametrically, it is important that the proper model to ... -
Consumptive Use and Water Requirement of Soybeans
(American Society of Civil Engineers, 1986)Various components of hydrologic cycle, e.g., rainfall, runoff, seepage, soil moisture and evapotranspiration (ET) were measured daily in a soybean plot, grown in a weighing‐type lysimeter consisting of a -
Using Radar for Groundwater Investigation
(American Society of Civil Engineers, 1986)The feasibility of using ground‐penetrating radar (GPR) in coarsetexture soils to determine depth to the water table was demonstrated in separate studies in Massachusetts and Florida. In Massachusetts, two sites were chosen ... -
Rational Use of The FAO Blaney‐Criddle Formula
(American Society of Civil Engineers, 1986)The FAO Blaney‐Criddle (FAO‐BC) evapotranspiration equation was calibrated and tested against a Penman combination equation with local wind function and daily lysimeter measurements of alfalfa evapotranspiration. Agreement ... -
Lateral Weirs in Trapezoidal Channels
(American Society of Civil Engineers, 1986)The theory of lateral flow through a two‐dimensional channel outlet is used to derive an expression for the outflow through a trapezoidal lateral weir discharging from a trapezoidal channel. The analysis is an extension ... -
Erratum: “Electronic Clocks for Timing Irrigation Advance” by Allan S. Humpherys, Michael D. Wilson, and Thomas J. Trout (March, 1985)
(American Society of Civil Engineers, 1985) -
Brink Depth in Nonaerated Overfalls
(American Society of Civil Engineers, 1985)Small drop structures employed in irrigation canals are often not ventilated. In this paper the importance of the residual pressure at the brink of a rectangular overfall is quantified by means of the 1‐D momentum equation. ... -
Artesian and Anisotropic Effects on Drain Spacing
(American Society of Civil Engineers, 1986)Subsurface drainage systems installed in soil overlying artesian aquifers should be spaced to handle both upward artesian water flow and normal downward seepage flow from irrigation and rainfall. Proper drain spacing depends ... -
Effects of Clay‐Solution Interactions on Water Retention
(American Society of Civil Engineers, 1986)Capillary pressure‐saturation data were measured on unconsolidated porous media containing 40% montmorillonite, as a function of total electrolyte concentration and sodium adsorption ratio (SAR) of the wetting fluid. Data ... -
Closure to “<i>Data Requirement for Evapotranspiration Estimation</i>” by Sun F. Shih (September, 1984)
(American Society of Civil Engineers, 1985) -
Evapotranspiration Model for Semiarid Regions
(American Society of Civil Engineers, 1985)The Thornthwaite method for calculating evapotranspiration (ET) as used in the water management model, DRAINMOD, is modified for semi‐arid conditions since for such conditions the existing method had underestimated the ...